1. Field of the Invention
The present invention relates to a liquid crystal display panel, and more particularly, to a liquid crystal display panel capable of improving a picture quality and reducing power dissipation.
2. Description of the Related Art
Generally, liquid crystal displays (LCDs) control light transmittance characteristics of liquid crystal material using electric fields to display pictures. Accordingly, LCDs typically include an LCD panel having a plurality of liquid crystal cells arranged in a matrix pattern and a drive circuit for driving the LCD panel.
The LCD panel includes a plurality of gate lines and a plurality of data lines arranged so as to cross one another, wherein the liquid crystal cells are defined by the gate and data lines. The liquid crystal display panel is further provided with a common electrode and a plurality of pixel electrodes for applying the electric fields to the plurality of liquid crystal cells to display pictures. The drive circuit includes a gate driver for driving the plurality of gate lines, a data driver driving the plurality of data lines, a timing controller for applying timing control signals and pixel data to the gate and data drivers, respectively, and a power supply for applying power voltage.
FIG. 1 illustrates a related art a liquid crystal display.
Referring to FIG. 1, the LCD includes an LCD panel 2 having a plurality of liquid crystal cells (Clc) arranged in a matrix pattern; a gate driver 4 for driving a plurality of gate lines GL1 to GLn within the liquid crystal display panel; and a data driver 6 for driving a plurality of data lines DL1 to DLm within the liquid crystal display panel 2.
The liquid crystal display panel 2 generally includes a plurality of thin film transistors (TFTs) arranged, similar to the liquid crystal cells Clc, in a matrix pattern at crossings of the gate lines GL1 to GLn and data lines DL1 to DLm. The TFTs apply pixel signals from the data lines DL1 to DLm to the liquid crystal cells Clc in response to scan signals applied from the gate lines GL1 to GLn. The liquid crystal cell (Clc) includes a pixel electrode connected to the thin film transistor and facing a common electrode, wherein the liquid crystal material is provided therebetween. The liquid crystal cell can be equivalently expressed as a liquid crystal capacitor.
The gate driver 4 generates scan signals and sequentially applies the scan signals to the gate lines GL1 to GLn in response to gate control signals outputted from a timing controller 8.
The data driver 6 converts digital pixel data outputted from the timing controller 8 into analog pixel signals in response to data control signals outputted from the timing controller 8. Further, the data driver 6 converts the digital pixel data into analog pixel signals using gamma voltages applied from a gamma voltage generator (not shown). Still further, the data driver 6 applies the analog pixel signals to the data lines DL1 to DLm whenever the scan signal is applied to any of the gate lines GL.
The gate control signals and data control signals generated by the timing controller 8 are used as vertical synchronization signals and horizontal synchronization signals to control the timing of the gate driver 4 and data driver 6. Further, the timing controller 8 receives and aligns externally inputted pixel data and outputs the aligned pixel data to the data driver 6.
Typically, liquid crystal display panels are driven according to an inversion driving method (e.g., a frame inversion method, a line (or column) inversion method, and a dot inversion method) to improve display quality as well as to prevent liquid crystal material from deteriorating.
FIGS. 2A and 2B illustrate a method of driving a liquid crystal panel display according to a frame inversion method.
Referring to FIGS. 2A and 2B, upon driving the LCD panel according to the frame inversion method, the polarity of all the liquid crystal cells within the LCD is identical and is inverted between frames. Driving the LCD panel according to the frame inversion driving method is problematic in that a flicker occurs between each frame.
FIGS. 3A and 3B illustrate a method of driving a liquid crystal panel display according to a line inversion method.
Referring to FIGS. 3A and 3B, upon driving the LCD panel according to the line inversion method, the polarity of liquid crystal cells within a horizontal line is identical, wherein polarities of adjacent ones of horizontal lines of liquid crystal cells are opposite, and wherein the polarities of the liquid crystal cells are inverted between frames. Driving the LCD panel according to the line inversion method is problematic in that a flicker occurs, generating a horizontal stripe pattern due to the crosstalk phenomenon between adjacent horizontal lines of the liquid crystal cells.
FIGS. 4A and 4B illustrate a method of driving a liquid crystal panel display according to a column inversion method.
Referring to FIGS. 4A and 4B, upon driving the LCD panel according to the column inversion method, the polarity of liquid crystal cells within a vertical line is identical, wherein polarities of adjacent ones of vertical lines of liquid crystal cells are opposite, and wherein the polarities of the liquid crystal cells are inverted between frames. Driving the LCD panel according to the column inversion method is problematic in that a flicker occurs, generating a vertical stripe pattern due to the crosstalk phenomenon between adjacent vertical lines of liquid crystal cells.
FIGS. 5A and 5B illustrate a method of driving a liquid crystal display panel according to a dot inversion method.
Referring to FIGS. 5A and 5B, upon driving the LCD panel according to the dot inversion method, the polarities of horizontally and vertically adjacent ones of the liquid crystal cells are opposite each other and are inverted between frames. Driving the LCD panel according to the dot inversion method may improve the picture quality of the LCD panels over the picture quality of LCD panels driven according to the other inversion methods because, when applying the dot inversion method, flicker occurs in both horizontal and vertical directions and therefore offset each other.
In driving the LCD panel according to the dot inversion method, the polarities of the analog pixel voltage signals applied from the data driver to the data lines are inverted in horizontal and vertical directions. Accordingly, driving the LCD panel according to the dot inversion method is disadvantageous because a fluctuation amount of the applied analog pixel signal (i.e., the frequency of the analog pixel signal) is greater than a fluctuation amount of the applied analog pixel signal in other inversion methods. Due to the large fluctuation amount of the applied analog pixel signal, power dissipation of the LCD panel is excessively high.